Loans - Average Recorded Investment - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	$ 15,744	$ 19,415	$ 16,244	$ 20,025
Interest Income Recognized on an Accrual Basis on Impaired Loans	78	59	162	118
Interest Income Recognized on a Cash Basis on Impaired Loans	2	100	2	193
Commercial, financial, and agricultural
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	1,931	5,298	2,049	5,286
Interest Income Recognized on an Accrual Basis on Impaired Loans	0	2	1	2
Interest Income Recognized on a Cash Basis on Impaired Loans	0	44	0	82
Real Estate Mortgages \| Residential
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	5,602	4,078	5,793	4,122
Interest Income Recognized on an Accrual Basis on Impaired Loans	57	27	114	55
Interest Income Recognized on a Cash Basis on Impaired Loans	0	22	0	39
Real Estate Mortgages \| Commercial
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	7,992	9,894	8,186	10,484
Interest Income Recognized on an Accrual Basis on Impaired Loans	20	30	46	61
Interest Income Recognized on a Cash Basis on Impaired Loans	0	33	0	69
Real Estate Mortgages \| Construction
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	62	72	63	73
Interest Income Recognized on an Accrual Basis on Impaired Loans	0	0	0	0
Interest Income Recognized on a Cash Basis on Impaired Loans	0	1	0	2
Consumer automobile loans
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	157	55	148	47
Interest Income Recognized on an Accrual Basis on Impaired Loans	1	0	1	0
Interest Income Recognized on a Cash Basis on Impaired Loans	2	0	2	1
Other consumer installment loans
Credit Quality and Related Allowance for Loan Losses
Average Investment in Impaired Loans	0	18	5	13
Interest Income Recognized on an Accrual Basis on Impaired Loans	0	0	0	0
Interest Income Recognized on a Cash Basis on Impaired Loans	$ 0	$ 0	$ 0	$ 0

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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